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medicine and quality monitoring, was reported rarely. Though several literatures have reported the thermal behavior of enoxacin [ 4 – 6 ] and its metal complexes [ 7 ], due to adopting only thermal analysis technique and the single heating rate method, it

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thermo-infrared spectroscopy analysis. Based on these analyses, the kaolinite–DMSO intercalation complex of a low defect (well crystallized) kaolinite from Zhangjiakou in China was prepared. The thermal behavior of the complex heated in different

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The thermal behaviour of the complexes of N,N-diethyl-N′-benzoylthiourea (DEBT) with Ni(II), Cu(II), Pt(II), Pd(II) and Ru(III) was studied using differential thermal analysis (DTA) and thermogravimetry (TG). These complexes undergo only a pyrolytic decomposition process. A gas chromatography-mass spectrometry combined system was used for the verification of the first decomposition product and X-ray diffraction method for the characterization of the final products of pyrolysis.

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Abstract  

Solid-state Ln(Bz)3·H2O compounds where Ln stands for trivalent yttrium or lanthanides and Bz is benzoate have been synthesized. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), X-ray powder diffractometry, infrared spectroscopy and chemical analysis were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, thermal stability and thermal decomposition of the isolated compounds.

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size of hematite has a strong effect on the thermal behavior of rutile and anatase-doped hematite ceramic systems, and the additions of rutile and anatase suppressed the crystallization of hematite [ 20 , 21 ]. The hematite with smaller particle sizes

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Abstract  

The complexes of the type M(HDMBG)2(CH3COO)2 nH2O ((1) M:Mn, n=1.5; (2) M:Ni, n=0; (3) M:Cu, n=2; (4) M:Zn, n=2; DMBG: N,N-dimethylbiguanide) present in vitro antimicrobial activity. The thermal analysis has evidenced the thermal intervals of stability and also the thermodynamics effects that accompany them. The different nature of the ligands generates a different thermal behaviour for the complexes. The thermal transformations are complex processes according to TG and DTG curves including dehydration, oxidative condensation of –C=N– units as well as thermolysis processes. The final products of decomposition are the most stable metal oxides.

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Journal of Thermal Analysis and Calorimetry
Authors: R. Macêdo, J. Barbosa-Filho, E. da Costa, and A. de Souza

Abstract  

The terpenoids acetyl sitosterol, lupeol, acetyl diosgenin and stigmasterol were studied. Comparison of the thermogravimetric curves and the activation energies of the terpenoids suggested the following sequence of thermal stability: acetyl sitosterol < acetyl diosgenin < lupeol < stigmasterol. The DSC curves allowed determination of the melting points and the degrees of purity. Comparison of the TG and DSC curves revealed the presence of phase transitions without mass loss that were attributed to rearrangements in the terpenoid molecules.

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Tin(II) complexes with 8-hydroxyquinolinate in solid state have been obtained by adding aqueous ammonium to a solution containing stannous chloride and 8-hydroxiquinoline in medium of HCl and acetone up to pH 5 and 9, respectively. The products obtained show the same composition, Sn(C9H6ON)2; however there are some differences regarding both the thermal behaviour in an oxidant atmosphere and morphology. These products were characterised by elemental and complexometric analysis, TG and DTA curves, infrared and X-ray diffractometry. TG curves show, above 448 K, the partial oxidation on air atmosphere of Sn(II) complexes to Sn(IV) complexes, SnO(C9H6ON)2. This behaviour does not depend only on pH in which the compounds were obtained but also on the heating rate in TG curves. Sn(II) complexes volatilise almost completely on nitrogen atmosphere and partially on air atmosphere depending on the oxidation degree of the compound.

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batteries by changing parameters about physical property, heat generation rate and environment [ 7 ]. Therefore, it is very important to study the thermal behavior of them. Modeling and simulation of the battery's thermal behavior are useful for obtaining

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Abstract  

Two methods are described in order to obtain copper-2,9-dimethyl-1, 10-phenanthroline (dmp) coordination compounds intercalated between the layers of α-Zr(HPO4)2·H2O and ψ-Zr(H2PO4)(PO4)·2H2O: the direct intercalation of Cu-dmp complex species or the formation ‘insitu’ of coordination compounds. With the first exchanger both methods lead to similar products with X-ray diffraction patterns practically identical. They contain Cu(II–I)-dmp complex species that confer to the solids an initially green colour slowly turning to yellow with time or temperature when the reduction of Cu(II) to Cu(I) is complete. With λ-ZrP(H2PO4)(PO4)·2H2O, only the direct insertion is successful. TG/DTA experiments permit a better understanding of what is occurring in the materials during the copper reduction step, in correspondance of which, a strong endothermic peak and a gain in weight can be observed. They also show how the difference in the structure and chemical formula of the two exchangers affect the thermal behaviour of the two series of compounds.

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